Pulverizing-mill



E. F. MCCUOLL PULVERIZING MILL. APPLICATION FILED JUNE 4, 1918- RENEWED MAR- 81 1920. 1,399,067. Patented'Dec. 6, 1921.

3 SHEETS-SHEET 1.

Qwuanfot E. F; McCOOL. PULVERIZING MILL. APPLICATION FILED JUNE 4. @918. RENEWED M'AR'. 8| I920.

--Patented Dec. 6, 192-1.

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lllllllll E.'F. M-cCOOL.

PULVERIZING MILL. I APPLICATION FILED 1m 4. 1918'. RENEWED MAR. s, 1920. 7 1 399 0 7 Patented Dec. 6, 1921,

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57 amen/ro e Eff. $6001 $46 I rarest @Fttfihi.

EDWARD IF. MOGOOL, OF CLEVELAND, OHIO.

PULVERIZING-MILL.

Specification of Letters Patent.

Patented Dec. 6, Lttteit.

Application filed. June 4, 1918, Serial No. 238,094. Renewed March 8, 1920. Serial No. 364,242.

To all whom it may concern Be it known that I, EDWARD F. MoCooL, a citizen of the United States, residing at Cleveland, county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Pulverizing-Mills; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to' make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this specification.

My invention relates to improvements in pulverizing mills, the construction being well adapted for very fine grinding, and while it may be employed for grinding materials of all kinds, as ore or similar substances, it is particularly well adapted for finely pulverizing coal preparatory to its delivery to furnaces as fuel.

As illustrated in. the drawing, my im provement is applied to a form of construction in which two grinding members in the form of disks are arranged to cooperate, one of them being preferably relatively stationary and the other rotatable, the rotary disk being mounted on one extremity of a shaft which is eccentrically mounted in a hollow shaft or sleeve which is also rotatable. lVhen the machine is in operation, both shafts are rotated, whereby the shaft-carrying the disk is given two movements, one a rotary movement on its own axis and the other an orbital travel with the hollow shaft, its axis during this movement describing a circle concentric with the axis of the hollow shaft.

My present improvement relates more particularly to certain features of adjustment in connection with the grinding disks or members, whereby the performance of the function of the structure is facilitated or enhanced. One of these features consists in the employment of a ring surrounding the stationary disk and cotiperating with the outer portion of the rotary disk, to control the mesh or fineness of the ground material. In constructions of this character the rotary disk is adjustable with its shaft, whereby it may be positively shifted toward its cooperating stationary disk. As the disks become worn and the rotary disk is made to approach the stationary disk the ring surrounding the latter and serving to determine the fineness of the ground material, is also adjustable to maintain a uniform width of space through which the ground material must pass before leaving the grinding members. An important feature of my present improvement consists in construction whereby both of these adjustments are automatically accomplished through the medium of bell crank lever constructions, one arm of each lever carrying a weight adjustable with reference to the fulcrum or axis, whereby the necessary pressure through the medium of an arm which engages the part to be ad justed, is accomplished. I have found it practicable to. effect this adjustment auto matically, while on the contrary I have found it difficult to obtain the desired results by relying upon manual adjustment for the purpose stated. With. my present improvement no special skill is required on the part of the operator in connection with these adjustments, since when the mechanism is once assembled and the weight properly adjusted on one of the arms of each lever construction, the adjustment during the use of the machine is entirely automatic.

I-Iaving briefly outlined my improvement I will proceed to describe the same in detail, reference being made to the accompanying drawing, in which is illustrated an embodiment thereof. In this drawing:

Figure l is a vertical longitudinal section taken through a pulverizing mill equipped with my improvement.

Fig. 2 is a horizontal section taken on the line 2-2, Fig. 1.

Fig. 3 is a horizontal section taken on the line 3-3, Fig. 1.

Fig. 4: is a face view of the rotary disk or a View looking in the direction of arrow a, Fig. 1.

Fig. 5 is a similar view of the stationary disk together with the adjacent hinged head of the mill upon which the said disk is mounted.

Fig. 6 is an end view of the mill looking work of the mill in which is j ournaled a hollow shaft or sleeve 6, a shaft 7 being eccen- 6 is rotated through the medium of a pulley 8 which is keyed to the sleeve as shown at 9. The shaft 7 is rotated through the medium of a pulley 10 which is operatively connected with the shaft 7 through the medium of a short sleeve 12, to which the pulley is keyed as shown at 13, the extremity of the sleeve remote from the pulley being provided with lugs 14 which interlock with spaced project'- tions 15 formed on a collar 16 keyed to the shaft 7, as shown. at 17.

As illustrated in this drawing, the two shaft-S 6 and 7 are independently rotated through the medium of their respective pulleys 8 and 10, though it is evident that for the purposes of the subject matter of this application the two shafts may be otherwise rotated if desired. To the forward extremity of the hollow shaft or sleeve 6 is secured, as shown at 18, a fan 19 having arms 20 to which are secured blades 21 which are located in the outer portion of the chamber 22 in which the pulverizing disks or members 23 and 24 are located, the fan blades when in operation moving around the pulverizing members and serving to discharge the pulverized material through an outlet nozzle 25. The pulverizing member 28 is connected, as shown at 26 with the forward extremity of the shaft 7 whereby as the said shaft rotates, a corresponding movement is imparted to the disk. The connection between the shaft and. the disk is also such as to allow a limited rocking movement of the disk upon the curved or rounded extremity 27 of the shaft. As illustrated, the grinding members 23 and 24 are recessed, as shown at 28 and 29, to receive balls 3 which cotiperate with the disks or grinding members to perform the pulverizing function. The grinding member 24 is connected with the head 30 of the mill by means of stud bolts 31 which are anchored in the grinding member and pass through openings 32 formed in the said head, nuts 33 being applied to the outer extremities of these bolts for fastening purposes. V

Extending transversely across the head 30 and horizontally positioned, is a bar 37 whose outer extremities are perforated to receive threaded portions 39 of bolts 40, nuts 41 and 42 being applied to the said threaded portions of the bolts on opposite sides of the bar. The threaded portions of these bolts pass through and move freely in unthreaded openings 43 formed in the head 30, their inner extremities 44 being anchored in openings 45 formed in a ring 46 surrounding and directly engaging the outer edge of the stationary grinding member. This ring 46 cooperates with the outer edge of the grinding member 24 to regulatethe mesh or fineness to which the material must be ground before it can escape from the grinding jaws. As the disks wear during use, an endwise adjustment of the shaft '7 is necessary in order to cause it to approachthe stationary grinding member, whereby a corresponding movement is imparted to the disk 23, in order to compensate for the wear of the parts and maintain the two grinding members 23 and 24 in such proximity that the balls 3 will rotate, and therefore, properly perform their function in the grinding operation when the mill is in use. I Asillustrated in the drawing, this endwise adjustment of the shaft 7 is accomplished through the medium of a nonrotatable thrust block A, one extremity of which is engaged by a movable pin B which protrudes beyond the adjacent extremity of the mill, while its opposite extremity engages the adjacent extremity of the shaft 7 through the medium of a ball bearing C. The outer extremity of the pin B is acted. on by the extremity E of a lever arm F whose opposite extremity is made fast to a rock shaft G journaled in arms H which extend outwardly from the adjacent extremityv of the mill on opposite sides of the pin B. The shaft G is further j ournaled in a third arm I. Another crank arm J is secured to the rock shaft G by means of a set bolt K which passes through a sleeve formed upon the arm J into engagement with the shaft. By virtue of this construction the crank arm J is rotatably adjustable on the shaft to vary its position as circumstances may require. The arm J is relatively long and carries a slidable weight L of suitable mass which is adjustable on the arm by means of a set bolt M. By virtue of this construction the weight L acts through the medium of the parts described to constantly exert the desired predetermined pressure in an endwise direction upon the shaft 7 in order to maintain the grinding member 23 in proper cooperative engagement with the companion grinding member 24, in order to cause themembers and the balls 3 acting in coijperation therewith,.to properly perform their function.

During the endwise shaft 7, as explained in the preceding para graph, if the ring 46 should maintain its original position, the space 47 for the of the pulverized material would be closed, or at least improperly reduced. Hence, in order to maintain the space 47 of uniform width, it becomes necessary to adjust the ring 46 in such a manner as to permit it to move forwardly or away from the rotary disk. This is accomplished through the medium of the movable connection of the adjustment of the' escape bolts l0 with the head and a bell crank lever N fulcrumed, as shown at O, on the hopper portion of the head 30 of the machine, one arm P of this lever acting on the central portion of the bar 87, as shown at Q, while its opposite arm R is equipped with a weight S which is so adjusted on its arm as to exert the necessary pressure on the said bar to maintain the ring 46 in propercooperative adjustment with the adjacent portion of the grinding member 23, this adjustment being entirely automatic and the parts being arrangedv to cause them to act in suitable cooperative relation with the mechanism at the opposite extremity of the mill which acts on the shaft 7, as heretofore explained. By virtue of the lever mechanism arranged at the opposite extremities of the mill, it will be understood that the adjustment of the mechanism after the parts have been prop erly set, is entirely automatic and compensates for wear upon the grinding members during such operation.

Ihe head 30 together with the relatively.

stationary disk 24: and their attachments is hinged, as shown at 48, whereby the head and the disk may be swung outwardly whenever it may be desirable to do so. This headis hinged through the medium of a perforated lug 19 carried by a ring 50 which is con-- nected to a casing 51 of the fan chamber by cap screws 52. By loosening these cap screws and unscrewing other cap screws 53 which connect the fan chamber with the main frame work of the machine, the fan chamber may be adjusted rotatably in order to bring the discharge nozzle 25 into position for discharging the pulverized material in any desired direction. After this adjustment is made, the screws 52 and 53 are again tightened to secure and maintain the fan chamber in the adjusted position.

From the foregoing description the use and operation of my improved mill will be readily understood. The hollow shaft 6 is rotated by applying power to the pulley 8 which is directly connected with the said shaft, whereby an orbital travel is imparted to the eccentrically mounted shaft 7. At the same time rotary movement on its own axis is imparted to the eccentrically mounted shaft 7 through the medium of the pulley 10. By virtue of this construction, the grinding member 23 is rotated on the axis of the shaft 7, while a gyratory travel is imparted to it by virtue of the orbital travel of the shaft 7. In practice the rotation of the hollow shaft 6 is relatively rapid, whereby the necessary speed is given to the fan 20 in order to expel the pulverized material through the nozzle 25 and cause the material to pass to the desired destination. If coal is pulverized, the material is delivered in regulated quantities to the fire box of a furnace (not shown), the feeding of the pulverized coal tothe furnace being so regulated that it is continuous. After the mill has been operated for a considerable time the faces of the grinding member will become sufliciently worn to require adjustment to compensate for such wear. This adjustment is automatically effected through the medium of the mechanism arranged at the opposite extremities of the machine and heretofore described, the automatic endwise adjustment of the shaft 7 being relied upon to maintain the two grinding members 23 and 24 in proper cooperative engagement, while the action of the bell crank lever N upon the bar 37 maintains the ring 46 in proper cooperative relation with the grinding member 23, in orderto properly control the fineness of the productwhich passes from the grinding members into the fan chamber.

The stud bolts 31 which connect the grinding member 2 1 with the hinged head of the mill are threaded into openings 56 formed in blocks 57 of relatively soft metal, as soft iron, the body of the grinding member being formed of hard steel or iron. By virtue of the stud bolt connection between the head and the relatively stationary grinding member the latter is rotatably adjustable on the head and in relation to its cooperating grinding member, whereby the relative positions of the oppositely located parts of the faces of the two grinding members, may be varied or changed-at intervals to facilitate the performance of the grinding function, regardless of the wear to which they are normally subjected. In other words, by this adjustment new surfaces of the one grinding member are brought opposite surface parts of the cooperating grinding member, thus overcoming or obviating the wearing of the two members in such a manner as to prevent ineflicient grinding, due to such wearing or grooving of these members.

Attention is called to the fact that the pressure exerted upon the thrust block A and upon the rotary grinding member through the medium of the shaft 7, should be greater than that exerted upon the peripherally arranged ring 46, since the object of the endwise pressure of the shaft 7 is to compensate for the wear of the two grinding members, and this pressure must bring the two grinding members into proper cooperative relation to rotate the balls 3. Consequently, if necessary the ring 46 must yield to the pressure of the rotary grinding member, otherwise the rotary member could not necessarily be brought into proper cooperative relation with the opposing or stationary member which the ring 46 surrounds.

Having thus described my invention, what I claim is:

1. A pulverizing mill including two cooperating grinding members, one being movable toward and away from the other, one of members being rotable, a head, bolts passing through said head, a ring peripherally arranged on the stationary member and supported by said bolts, the latter being movable in the head, a bar connecting the said bolts, and means acting on the bar to automatically adjust the ring, to regulate the discharge space. i i

3. A pulverizing mill including two cooperating grinding members, one being movable toward and away form the other, the

other member being surrounded by a ring, bolts supporting the said ring, a head in which the said bolts are movable, a tranverse bar connecting the two bolts and a bell crank lever fulcrumed on the head, one arm of the lever engaging the said bar, while the other arm is weighted to cause the bar-engaging arm to exert the necessary pressure for the adjustment of the ring to cause the latter to properly cooperate with the opposing member.

4E. A pulverizing mill including operating grinding members, an movable shaft with which one of the said members is connected in operative relation, means for automatically adjusting the said shaft in an endwise direction to compensate for the wear of the two members, said means being arranged to exert a predetermined pressure on the shaft for the aforesaid purpose, a ring peripherallv arranged with reftwo coendwise member.

erenee to the other grindingmember, and' means for automatically exertinga predetermined pressure on the said ring, the arrangement being such that the pressure exerted on the shaft is greater than that exerted on the ring.

5. A pulverizing mill including two 00- operating grinding members, one being movable toward and away from the other, a movable ringsurrounding the other member, means for automatically forcing said movable grinding member toward the cooperating member, and other means for automatically forcing said ring toward said movable member.

6. A-pulverizino mill including two cooperating grinding members, one being movable toward and away from the other, a movable ring surrounding the other member, means for automatically forcing said movable member toward said stationary member under an adjustable predetermined pressure, and means for automatically forcing said ring toward said movable member under adjustable predetermined pressure less than the pressure on said movable member.

7. A pulverizing mill comprising a stationary grinding member, a cooperating rotatable grinding member movable toward 'and away from said stationary member, means for forcing said movable member toward said stationary member under a predetermined pressure, a movable ring surrounding said stationary member, and means for automatically forcing said ring toward said movable member, said means being adapted to be set at predetermined pressures less than the pressure actuating said movable In testimony whereof I afiix my signature.

EDWARD F. MoCOOL. 

